Excluding location from rewrite

I'm running a VBulletin forum on my webserver, and in order to leverage the VBSeo plugin (which rewrites thread paths into more search engine friendly paths), I had to add these rewrites to "location /".

This works fine for all locations that are controlled by Vbulletin, but if I were to add my own php file within my site root, I can not seem to get it to be served by nginx. What I'm looking to do is run a few custom php pages that will not be forwarded through the VBSeo rewrites, but I'm not sure how to do that.

I'm looking to add /donate as a location that is not included in the above rewrites, and serve index.php from within that directory. Any help or suggestions are much appreciated. I am by no means a webserver expert, and I'm still relatively new to nginx.